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Can we really measure the ecological footprint of the Olympics?

Marie Delaplace
Marie Delaplace
Emeritus Professor of Spatial Planning at Université Gustave Eiffel
Martin Müller
Martin Müller
Professor of Geography at the University of Lausanne
Key takeaways
  • The organisers of the Paris 2024 Olympic Games are promising to halve CO2 emissions compared with previous Summer Games.
  • None of the recent editions of the Olympics have achieved the environmental targets initially promised.
  • While a study of the London Games showed that the majority of environmental indicators were positive or negligible, the scientific community remains divided on the overall sustainability of the Games.
  • The main source of greenhouse gas emissions from the Games is from visitor flights, followed by the construction of new buildings.
  • To reconcile the Olympics and sustainability, several measures need to be considered, including staging the Games in the same cities and broadcasting them around the world.

The French cap­i­tal is prepar­ing to host the Olympic Games. With an ath­letes’ vil­lage, sports facil­i­ties and mil­lions of vis­i­tors to wel­come, it is hard to ignore the envi­ron­men­tal impact of such an event. “The main source of green­house gas (GHG) emis­sions from the Olympic Games is from vis­i­tor flights, fol­lowed by the con­struc­tion of new build­ings,” explains Mar­tin Müller. The organ­is­ers are promis­ing to lim­it emis­sions: while the pre­vi­ous Sum­mer Games emit­ted between 3 and 4 mil­lion tonnes of CO2 equiv­a­lent (CO2e, a unit that includes all green­house gas­es), Paris 2024 is promis­ing to halve this figure.

Hold­ing this sort of an event will always have more of an impact than if it didn’t take place.

It must be said that this is not a new issue, and the Inter­na­tion­al Olympic Com­mit­tee (IOC) – the organ­is­ing body of the mod­ern Games – has also made it a pri­or­i­ty. Sus­tain­abil­i­ty is one of the pil­lars of the 2020 Olympic Agen­da 2020, the IOC’s strate­gic roadmap, and the organ­is­ing cities have a duty to demon­strate the sus­tain­abil­i­ty of the event. “It is impor­tant to reduce green­house gas emis­sions, but to say that the Games are sus­tain­able makes no sense: hold­ing this sort of an event will always have more of an impact than if it didn’t take place,” asserts Marie Delaplace.

What exact­ly are these impacts? A team from the Uni­ver­si­ty of East Lon­don car­ried out an impact study1 on the Lon­don 2012 Sum­mer Games for the IOC. Of the 67 indi­ca­tors con­sid­ered, 15 con­cerned envi­ron­men­tal impact. For ten of them, the Games had a pos­i­tive impact: the cre­ation of green spaces thanks to the rede­vel­op­ment of a for­mer indus­tri­al waste­land, improve­ments to the rail infra­struc­ture (par­tic­u­lar­ly in East Lon­don), new waste treat­ment facil­i­ties (par­tic­u­lar­ly haz­ardous waste), an increase in the sup­ply of accom­mo­da­tion and the sus­tain­abil­i­ty of new build­ings. As for the oth­er sev­en, they are assessed as being neg­li­gi­ble: water qual­i­ty in the Riv­er Lee, air qual­i­ty, land use, etc. And even GHG emis­sions thanks to emis­sions off­set­ting ini­tia­tives (which amount­ed to 3.3 mil­lion tonnes CO2e). No indi­ca­tor has a neg­a­tive impact. Over­all, the authors gave the event an aver­age sus­tain­abil­i­ty rat­ing (0.56 out of 1) for the envi­ron­men­tal indi­ca­tors, three years after the Games were held.

A question without scientific consensus

But the sci­en­tif­ic com­mu­ni­ty is divid­ed on the issue of the sus­tain­abil­i­ty of the Olympic Games. “In essence, they fol­low a prin­ci­ple of growth, which runs counter to the main prin­ci­ple of sus­tain­abil­i­ty, name­ly the idea of liv­ing well while lim­it­ing the con­sump­tion of resources,” says Mar­tin Müller. Nev­er­the­less, the debate con­tin­ues among sci­en­tists, as Mar­tin Müller and his col­leagues describe in the jour­nal Nature sus­tain­abil­i­ty2: for some, mega-events like the Olympics rep­re­sent an oppor­tu­ni­ty to pro­mote and present inno­v­a­tive solu­tions to glob­al chal­lenges, and are polit­i­cal levers towards sustainability.

How can we assess the real impact of an event like this? “The term “cli­mate neu­tral­i­ty” is some­times used, but this is a mar­ket­ing term based on car­bon account­ing: off­set­ting emis­sions by buy­ing car­bon cer­tifi­cates,” explains Mar­tin Müller. “Research has shown that many of these cred­its are unre­li­able and do not com­pen­sate for what they promise.” Although the IOC is ask­ing cities to demon­strate their sus­tain­abil­i­ty, sci­en­tists believe that the organ­i­sa­tion is inca­pable of guar­an­tee­ing envi­ron­men­tal­ly sus­tain­able Olympic Games3: none of the recent edi­tions of the Games has achieved the envi­ron­men­tal objec­tives ini­tial­ly promised. Rio 2016, Bei­jing 2008, Van­cou­ver 2010, Lon­don 2012 or Sochi 2014: the authors pro­vide a long list of ref­er­ences to back up their find­ings. “The indi­ca­tors con­sid­ered by the IOC are far too gen­er­al and glob­al,” adds Marie Delaplace. “Rather than think­ing in terms of impact, which implies a causal rela­tion­ship, it is more rel­e­vant to talk about co-pro­duc­tion. This reflects what hap­pens dur­ing an event which, in fact, is anchored in time and space. This requires us to rea­son on a micro-ter­ri­to­ry scale.”

Look­ing at the 16 edi­tions of the Olympic Games held between 1992 and 2020, Mar­tin Müller and his col­leagues assess the sus­tain­abil­i­ty of the Games. Sus­tain­abil­i­ty is defined by a lim­it­ed eco­log­i­cal and mate­r­i­al foot­print, improved social jus­tice and eco­nom­ic effi­cien­cy. Over­all, sus­tain­abil­i­ty is aver­age (reach­ing a score of 48/100). Eco­log­i­cal indi­ca­tors are even worse, scor­ing 44/100. Worse still, the authors show that sus­tain­abil­i­ty – and par­tic­u­lar­ly eco­log­i­cal aspects – has been declin­ing since 1992. Sochi 2014 and Bei­jing 2008 received the worst scores for eco­log­i­cal aspects. Con­verse­ly, Albertville 1992, Barcelona 1992, Salt Lake City 2002 and Athens 2004 achieved the best eco­log­i­cal scores.

Post-Olympic Games: infrastructure legacy

On the oth­er hand, the “long-term via­bil­i­ty” indi­ca­tor, based on the use of the facil­i­ties after the event, scores high­ly (76/100). It rais­es anoth­er impor­tant issue: what is the lega­cy of these events? The Paris 2024 organ­is­ers state, for exam­ple, that the Ath­letes’ Vil­lage, built on a for­mer indus­tri­al waste­land, will be trans­formed into a sus­tain­able dis­trict of the city4. “A sim­i­lar trans­for­ma­tion has tak­en place in Lon­don: there are a num­ber of debates around the gen­tri­fi­ca­tion of the area ver­sus social mix,” says Marie Delaplace. “The same con­tro­ver­sies are now play­ing out regard­ing Seine-Saint-Denis.” Some of the facil­i­ties built for the Games (notably pub­lic trans­port) are of use to the local pop­u­la­tion after­wards, as was the case in Lon­don, but their use­ful­ness is more dis­put­ed in Rio and Athens. “The ques­tion of the lega­cy of the Games is not easy to assess: the dif­fi­cul­ty lies in hav­ing data that is suf­fi­cient­ly old to iden­ti­fy the true tra­jec­to­ry of the co-pro­duc­tion of the lega­cy of the Games,” adds Marie Delaplace. “Some projects would have tak­en place with­out the Games, while oth­ers were imple­ment­ed dur­ing the city’s pre­vi­ous bids. It is dif­fi­cult to iden­ti­fy the actu­al start­ing point.” Mar­tin Müller adds: “It is the­o­ret­i­cal­ly pos­si­ble to take advan­tage of these events to accel­er­ate low-car­bon tran­si­tions, for exam­ple by intro­duc­ing clean ener­gy more quick­ly. But lit­tle research has been car­ried out, and pre­vi­ous stud­ies have shown that the Olympic Games pro­duce show­case effects, but fail to accel­er­ate more impor­tant struc­tur­al changes.”

Are there ways of rec­on­cil­ing cli­mate change mit­i­ga­tion and the Olympic Games? The sci­en­tists sug­gest sev­er­al approach­es. First­ly, gov­er­nance, to cor­rect the IOC’s lack of effec­tive incen­tives for sus­tain­abil­i­ty. While the envi­ron­men­tal impact of new con­struc­tion is unde­ni­able, some sug­gest that the Games should be held in rota­tion in the same cities. “An impor­tant step would be to bring the Olympic Games to the peo­ple, rather than bring­ing the peo­ple to the Olympic Games,” con­cludes Mar­tin Müller. “The idea would be to have much small­er sta­di­ums and for vis­i­tors to enjoy the Games in fan zones around the world, rather than trav­el­ling by plane”

Anaïs Marechal
4Web­site con­sult­ed on June 7, 2024: https://​olympics​.com/​f​r​/​p​a​r​i​s​-​2​0​2​4​/​n​o​s​-​e​n​g​a​g​e​m​e​n​t​s​/​e​n​v​i​r​o​n​n​e​m​e​n​t​/​m​e​t​h​o​d​e​-​c​a​rbone

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